KAMPALA, July 13 (Reuters) - Ugandan police have found an unexploded suicide vest and arrested six of the more than 20 Somalis and Ugandans suspected of planning twin bombings that killed 76 soccer fans on Sunday, an intelligence source said.
Somali al Shabaab Islamists linked to al Qaeda said they had carried out the attacks on a crowded restaurant and a rugby club in the Ugandan capital while fans watched the World Cup final on television.
In Washington, a senior U.S. official said there were indications that al Shabaab’s claim of responsibility was authentic. It would mark the first time the group has struck outside Somalia.
U.S. President Barack Obama said it was "tragic and ironic" that the explosions happened as people were watching the World Cup being played in South Africa.
"On the one hand, you have a vision of an Africa on the move, an Africa that is unified, an Africa that is modernizing and creating opportunities," Obama told the South African Broadcasting Corp. "On the other hand, you’ve got a vision of al Qaeda and Al Shabaab that is about destruction and death."
Washington has been in contact with Uganda and other governments in the region to determine whether al Shabaab is plotting more attacks and to share intelligence and decide on all "appropriate measures," a senior U.S. official said.
An al Shabaab official said there had been no suicide bombers involved in the attack on Uganda, which has peacekeepers in Somalia.
A Ugandan military intelligence source told Reuters that intelligence officials had received a tip-off last month that an attack was being planned. But the U.S. official said Washington was not aware of any advance warning.
"On June 17 an informer from the Kisenyi suburb of Kampala told intelligence that some Somalis were planning an attack during the World Cup," the Uganda source said.
The official said more than 20 people, Somalis and Ugandans, were involved in planning the attacks. "So far we have arrested six people from that racket," he said.
Al Shabaab has threatened more attacks unless Uganda and Burundi withdraw their peacekeepers from the African Union peacekeeping force in Somalia, where the militants are fighting the government and control large parts of the country.
Police said the suicide vest found late on Monday at a third site was designed so it could be planted, rather than worn.
"Rage blessed those who carried the attack and expected a long life for them. That shows there was no suicide bomb. These were planted," a man who identified himself as Yonis, assistant to al Shabaab spokesman Sheikh Ali Mohamud Rage, told Reuters.
As well as banning alcohol, al Shabaab has prohibited watching soccer matches in areas under its control.
Coordinated attacks are a hallmark of al Qaeda and groups linked to Osama bin Laden’s militant network. But for al Shabaab, it would be the first time the militants have taken their push for power internationally.
AFRICAN SUMMIT
"I think that there’s a common recognition that this is a new phase for al Shabaab in terms of expanding their geographic reach unfortunately," U.S. Homeland Security Secretary Janet Napolitano told reporters.
"We are constantly looking at ways that we can increase our preparation for, prevention of, and interdiction of any type of terrorist attack before it should occur on our own soil," she said.
The U.S. official who briefed reporters in Washington said al Shabaab had been "on our radar screen," had links to al Qaeda in East Africa and al Qaeda in the Arabian Peninsula.
The official said the Kampala attack was in line with threats to broaden its targets, but did not directly answer a question whether the group might pose a specific danger to the United States.
"What you’ve seen in some of the statements that have been made by these terrorist organizations is that they do not regard African life as valuable in and of itself," Obama said in the interview with South African Broadcasting Corp.
"They see it as a potential place where you can carry out ideological battles that kill innocents without regard to long-term consequences for their short-term tactical gains."
The African Union said Uganda would still host a summit of African leaders this month and that it would not be deterred from its peacekeeping mission.
Regional bloc IGAD said it would not be cowed and would continue to support the Western-backed government in Somalia.
"We shall continue with our plans to increase peacekeepers in Somalia to over 8,000 and we hope to have the extra troops in the country by the second week of August," executive secretary Mahboud Maalim told journalists in the Kenyan capital Nairobi.
Last week IGAD members Kenya, Uganda, Sudan, Ethiopia, Somalia and Djibouti said they eventually wanted 20,000 troops from the AU and United Nations deployed in Somalia.
Uganda’s opposition Forum for Democratic Change party urged President Yoweri Museveni to pull his peacekeepers out and said it planned a withdrawal if it won elections in 2011.
"There is no peace to keep in Somalia and Uganda has no strategic interest there. We’re just sacrificing our children for nothing," party spokesman Wafula Oguttu told Reuters.
Analysts say any sustained bombing campaign would damage Uganda’s investment climate, but a one-off attack was unlikely to deter major companies such as British hydrocarbons explorer Tullow Oil from investing.
Direct foreign investment in east Africa’s third largest economy has surged, driven by oil exploration along the western border with the Democratic Republic of Congo.
One American was among the dead. The U.S. embassy in South Africa said five other U.S. citizens who had been wounded had been evacuated to Johannesburg and Nairobi. An FBI team is in Kampala, the U.S. State Department said.
